VTL Replication

VCartridges in a VTL can be replicated to another QUADStor VTL system either manually or automatically. Automatic replication for VCartridges will be done when
1. If the storage pool of the vcartridge has the "Auto-Replication" property set
2. If the vcartridge belongs to a VTL and not a standalone virtual drive

Additional Requirements

The following are the additional requirements for a successful VTL replication operation
1. The destination VTL needs to have a storage pool whose name matches the pool name of the source vcartridge
2. Sufficient physical storage space needs to exist in the destination storage pool to store the entire vcartridge data.
3. If a vcartridge with the same name exists, then it needs to have the same size and vcartridge type as the source.
4. Ensure that the following ports are allowed for TCP traffic in your firewall configuration

9953
9955

Auto-Replication

Configuring the VTL system to receive replication traffic

Only IPv4 addresses are supported. Host names and IPv6 addresses are not allowed

Create a file called /quadstorvtl/etc/ndrecv.conf and add the following line

RecvAddr=<recv listening ipaddr>

For example

RecvAddr=10.0.13.6

In the above example, the system will bind to 10.0.13.6 for replication data

Configuring the VTL system to send replication traffic

Create a file called /quadstorvtl/etc/ndrecv.conf and add the following line

PeerAddr=<ipaddr to send to>

For example

PeerAddr=10.0.13.7

In the above example, the system send replication data to 10.0.13.7

For auto-replication of vcartridge data, the PeerAddr has to be set on the source VTL system and the RecvAddr has to be set on the destination VTL system.
When a backup application move a vcartridge into one of the virtual Import/Export ports, auto-replication is triggered for the vcartridge

Manual Replication (HTML UI)

To start a new replication job click on "Job Management". Under "Replication Jobs" click on "Add Job". A form as shown in the figure below is presented
Add Replication Job

  • If the destination vcartridge does not exist it will be created with the same properties as the source vcartridge.
  • If the destination vcartridge does not exist and a VTL with the same name as the source vcartridge VTL does not exist the VTL will also be created.
  • If the destination pool name is not specified then the storage pool name of the source vcartridge will be used.
  • Source IP address is optional and if specified, that address is used as the source for sending replication data, else any available ip address on the source VTL system is used.

    Click on "Submit" to start the replication job

    The list of replication jobs can be view from the "Job Managment" page under the "Replication Jobs" section as shown in the figure below.
    Add Replication Job

    The listed jobs also include the auto-replication jobs initiated by the system.

    Click on the Deleteicon to cancel a running replication job

    Click on "Clear Jobs" to clear all completed jobs, cancelled jobs and jobs which ended with an error status

    Manual Replication (Command Line)

    Set the RecvAddr property as described above for the destination VTL system.

    Use /quadstorvtl/bin/vtmirror to start the replication as follows
    /quadstorvtl/bin/vtmirror -s <Source VCartridge Name> -d <Destination VCartridge Name> -r <Destination IP Address> -s <Source IP Address> -g <Destination Pool>

  • If the destination vcartridge does not exist it will be created with the same properties as the source vcartridge.
  • If the destination vcartridge does not exist and a VTL with the same name as the source vcartridge VTL does not exist the VTL will also be created.
  • If the destination pool name is not specified then the storage pool name of the source vcartridge will be used.
  • Source IP address is optional and if specified, that address is used as the source for sending replication data, else any available ip address on the source VTL system is used

    Click on "Job Management" to view the list of replication jobs, which are lu

    For example:

    /quadstorvtl/bin/vtmirror -s VCART1 -d VCART1 -r 10.0.13.7 -g ARCHIVE
    

    In the above example vcartridge VCART1 is replicated to another vcartridge name VCART1 belonging to storage pool ARCHIVE on VTL system 10.0.13.7

    Managing replication jobs

    Listing replication jobs

    /quadstorvtl/bin/vtmirror -l will list basic job information annd /quadstorvtl/bin/vtlmirror -l -e will list extended information.
    For example

    # /quadstorvtl/bin/vtmirror -l
    Source   SAddr   Destination DAddr      Size       Time  Status   
    BCM201L4 0.0.0.0 BCM209L4    10.0.13.13 185.00 MB  8.6   Running  
    
    # /quadstorvtl/bin/vtmirror -l
    Source   SAddr   Destination DAddr      Size       Time  Status   
    BCM201L4 0.0.0.0 BCM209L4    10.0.13.13 187.00 MB  8.8   Completed
    
    # /quadstorvtl/bin/vtmirror -l -e
    Source   SAddr   Destination DAddr      Size       Time  Status    WriteT BytesW       Deduped      Encryped    
    BCM201L4 0.0.0.0 BCM209L4    10.0.13.13 187.00 MB  8.8   Completed 3.2    0.00 KB      187.00 MB    0.00 KB  
    

    In the above output
    Soruce is the source vcartridge
    SAddr is the source ip address used
    Destination is the destination vcartridge
    DAddr is the destination ip address
    Size is the total transfer size of the operation
    Time is the number of seconds since the operation started
    WriteT indicates the number of seconds spent in sending and writing data at the remote VTL
    BytesW indicates the number of bytes sent and written at the remote VTL
    Deduped indicates the number of bytes which were deduplicated at the remote VTL
    Encypted indicates the number of encrypted bytes sent.

    Clearing completed jobs

    /quadstorvtl/bin/vtmirror -l -p will list the jobs and will also clear completed jobs. So the next time vtmirror -l is run, the completed job will no longer show in the list

    Cancel a replication job

    /quadstorvtl/bin/vtmirror -s -c will cancel any replication operation running for the source vcartridge

    For example

    /quadstorvtl/bin/vtmirror -s BCM201L4 -c
    

    The above command will cancel any replication job running for vcartridge BCM201L4

    Notes

    1. Only one replication job can be started for a vcartridge at a time
    2. If there any pending import/export jobs for a vcartridge, replication cannot be started for the vcartridge
    3. Replication is not support for multi-partition virtual tapes (LTFS) and virtual tapes with encrypted data.